Democrats handed over one million signatures to Republican leadership Wednesday demanding that they and president-elect Donald Trump leave Medicare alone.

Medicare is a federal program providing insurance to seniors and people with disabilities. Republicans have argued the program is in desperate need of reform. Democrats defended the program during a rally before advocates delivered the signatures to Republican leaders Sen. Mitch McConnell and Speaker Paul Ryan.

“Destroying Medicare and making seniors pay more is not what Americans voted for in the November election,” House Minority Leader Nancy Pelosi said during the event. “Today we will give a stern message to Republicans in the Congress. We will not stand by while Republicans dismantle the promise of a healthy and dignified retirement.”

Republicans have long argued Medicare is structurally and financially unstable. Ryan and others have suggested reforming Medicare to preserve the program for future generations. Medicare beneficiaries under the plan would buy insurance from multiple competing plans. Critics have contested the idea will upend the program and hurt those that rely on it.

“We’re going to need everyone, everyone, to stand together next year and fight any attempts to privatize or weaken Medicare,” Democratic Sen. Chuck Schumer said during the event. “My friends, all sides suggests a fight is coming.”

Trump said during the campaign that he wasn’t like most in his party when it comes to Medicare. He promised he wasn’t going to cut the program and other social safety nets like Social Security. Democrats and other critics warn he might go back on that promise.

“Mr. Trump, we are going to hold you accountable,” Sen. Bernie Sanders said during the rally. “You said you would not cut Social Security, you would not cut Medicare, you would not cut Medicaid. You know what, millions of us are going to demand that you keep your promise.”

The petition signatures were collected by Social Security Works, Our Revolution, Alliance for Retired Americans, National Nurses United and JustCare, among other advocacy groups. Members of the organizations marched from the event to personally deliver the signatures to McConnell and Ryan.

“Forget about all your plans to voucherize Medicare, to raise the retirement age of social security, to slash Medicaid,” Sanders also said. “It ain’t gonna happen. And what we’re going to do is rally millions and millions of people for who Social Security, Medicare and Medicaid is life and death.”

Republicans will soon be in a position to significantly change Medicare. They were able to secure the presidency during the Nov. 8 election while also maintaining congressional control. Nevertheless, Democrats have vowed to do all they can to fight the reforms.

“I know, during the campaign president-elect Trump promised to save Medicare, Medicaid and Social Security,” Schumer said. “He even made it explicit that he disagreed with most Republicans in his party on these social security safety net programs. He even criticized them for their position. That was then. This is now.”

Trump last month nominated Republican Rep. Tom Price to lead the Department of Health and Human Services. Democrats warn the pick is a sign the president-elect is looking to go back on his promise to not touch Medicare. The Centers for Medicare and Medicaid Services is an agency within the department.

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